by Chiu Chi-Wai. / Thesis (M.B.A.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 75-78). / ACKNOWLEDGMENT --- p.ii / ABSTRACT --- p.iii / TABLE OF CONTENTS --- p.iv / LIST OF FIGURES --- p.vi / LIST OF TABLES --- p.vii / Chapter / Chapter I. --- INTRODUCTION --- p.1 / Objective --- p.1 / Background --- p.1 / Outline of Subsequent Sections --- p.2 / Summary of Conclusions --- p.3 / Chapter II. --- METHODOLOGY --- p.4 / Chapter III. --- PTA GLOBAL AND REGIONAL OUTLOOK --- p.6 / The PTA - Polyester Chain --- p.6 / Polyester Products --- p.6 / Polyester Raw Material Outlook --- p.8 / Asian PTA Supply and Demand --- p.9 / Conclusion: Asian PTA Supply and Demand --- p.11 / Chapter IV. --- COUNTRY ANALYSIS --- p.12 / Macroeconomics Overview --- p.12 / Regulatory and Investment Environment --- p.15 / India vs. China --- p.18 / Chapter V. --- MARKET ANALYSIS --- p.20 / PET Market --- p.20 / PTA Market --- p.24 / India PTA Supply and Demand --- p.26 / Conclusion: India PTA Supply and Demand --- p.27 / Chapter VI. --- TECHNICAL ANALYSIS --- p.28 / Oxidation --- p.28 / Purification --- p.29 / Chapter VII. --- ECONOMIC ANALYSIS --- p.31 / Review of Petrochemical Industry in India --- p.31 / Project Economics and Assumptions --- p.34 / Conclusion --- p.43 / Chapter VIII. --- PROJECT FUNDING ANALYSIS --- p.49 / Risk Factors --- p.50 / Principle Terms of Bank Syndication --- p.56 / Chapter IX. --- CONCLUSION --- p.58 / Current Environment and Future Trends --- p.58 / Investment Opportunity --- p.60 / Summary of Economic Analysis --- p.60 / Factors for Future Success --- p.61 / APPENDIX --- p.62 / BIBLIOGRAPHY --- p.75

L'objectif de ces travaux a été d'estimer les propriétés thermomécanique des revêtements abradables. Lesmatériaux abradables sont des structures fortement hétérogènes et le but a été de considérer leurs microstructuresdétaillées. L'intérêt de ces travaux a été de passer outre la difficulté de leur dimensionnement lors de l'élaborationdes couches. Trois revêtements abradables ayant différentes natures et différentes microstructures ont étéétudiées, la complexité de leur microstructure était différente les unes des autres. Leurs propriétés ont étédéterminées par une méthode de modélisation 2D appliquée directement pixel par pixel pour prendre enconsidération la microstructure détaillée. Afin de valider la méthode de modélisation, les résultats calculés ont étécouplés et comparés à des valeurs expérimentales. Deux méthodes de modélisations ont été appliquées : uneméthode conventionnelle; avec une image des revêtements représentant les détails de la microstructure aussi bienque la microstructure dans sa globalité ainsi qu'une méthode de modélisation 2-échelles, avec une première échellereprésentant les détails de la microstructure de la matrice et une seconde échelle représentant le revêtement globalet notamment la distribution des plus gros pores.Une des conclusions principales de ces travaux est la suivante : Si la complexité du matériau augmente, le nombred'échelle nécessaire pour décrire la microstructure réelle augmente. La méthode de modélisation 2 échelles a étévalidée à travers la comparaison entre les valeurs calculées et les résultats expérimentaux. Ces travaux ont aidé àobtenir un outil pour sélectionner digitalement les microstructures les plus prometteuses pour les applicationsd'abradabilité. Ceci permet de réduite le nombre de tests expérimentaux à effectuer. Ces tests expérimentaux sontplus longs à mettre en oeuvre et coutent plus cher. C'est un outil support quant au développement des structuresabradables. / The objective of this work was to estimate apparent thermomechanical properties of abradable coating. Abradablematerials are strongly heterogeneous structures and the aim was to consider their detailed microstructure. Theinterest of this work is to overstep one difficulty when manufacturing abradable coating which is their dimensioning.Three abradable coatings having different nature and different microstructures have been studied. Theirmicrostructure complexity was different one from each other. Their properties were determined by a 2D modelingmethod which was applied directly pixel by pixel to take account of all the microstructural details. To validate themodeling method, the results calculated were coupled and compared to experimental ones. Two modeling methodhave been applied, a conventional one, with coating image representing coating microstructural details as well asthe global coating microstructural distribution and a 2-scale modeling method, with one scale representing themicrostructural details of the matrix and a second on representing the global coating coarse pores distribution. Onemain conclusion of this work is the following one: If the material complexity increases, the number of scalemandatory to describe the real microstructure increases. The 2-scales modeling method has been validated throughcomparison of the calculated values with those obtained experimentally. This work helps to provide a tool for digitallyselect the most promising abradable layers with the effect of reducing the number of experimental tests, which arelonger and more expensive to implement. It is a tool for decision support in the abradable coating development.

Les résines polyesters sont des composants présents dans une majorité des revêtements et matériaux utilisés aujourd'hui. Ils sont obtenus par polycondensation de polyols, polyacides et monoacides. Les réglementations évoluant (REACH) et le public étant de plus en plus sensible à l'origine et l'impact des produits qu'il consomme, la substitution des produits pétrosourcés vers des matières premières renouvelables semble évidente. De nouveaux polyesters, composés majoritairement de monomères biosourcés, ont donc été synthétisés. L'acide L-(+)-tartrique a été principalement étudié, ce monomère quadri-fonctionnel étant peu utilisé dans la chimie des matériaux bien que disponible en grandes quantités et peu coûteux. Afin de caractériser les polyesters, différents tests utilisés dans l'industrie ont été mis en place, les caractéristiques physico-chimiques pouvant varier d'une application à l'autre. Différents mécanismes de réticulation ont également été explorés afin d'adapter les polyesters aux contraintes de résistance et de séchage requises. Ces mécanismes incluent la réaction entre les hydrazides et les méthyles cétones ainsi que celle des dérivés du Bore et des hydroxyles à température ambiante. La solubilité des polyesters synthétisés a également été étudiée afin d'obtenir un produit soluble en phase aqueuse capable de devenir insoluble après réticulation et séchage / Polyester binders are the main components of the coatings and materials used nowadays. They are obtained by the condensation of polyols, polyacids and monoacids. Evolving regulations (REACH) and the public being increasingly sensitive to the origin and impact of the products it consumes, petro based compounds substitution to renewable raw materials seems obvious. New polyesters, mainly composed of biobased monomers were therefore synthesized. The L-(+)-tartaric acid was mainly studied, this quad-functional monomer being barely used in materials chemistry, although available in large quantities and inexpensive. To characterize polyesters, various tests used in the industry have been established, the physicochemical characteristics may vary from one application to another. Different crosslinking mechanisms have also been explored to adapt polyesters constraints of resistance and drying. These mechanisms include the reaction between the hydrazide and methyl ketones, as well as the derivatives of Boron and hydroxyl at room temperature. The solubility of the synthesized polyesters was also studied in order to obtain a water soluble material capable of becoming insoluble after crosslinking and drying

Havsmiljöer är idag den slutliga anhalten för den nedskräpning av plast som kommer ifrån avloppsvatten och allmän nedskräpning. Stora mängder plastpartiklar i olika storlekar har upptäckts i haven och även inuti djur som misstagit plasten som föda. Forskning visar att en stor del av plasten är av mikroskopisk storlek, så kallade mikroplaster. Inom denna grupp förekommer textilfibrer som likt andra plaster är svårnedbrytbara i naturen. Det har genom studier påvisats att små textila fiber rinner ut med avloppsvattnet och hamnar i haven. PET är en av de vanligaste plasterna och utifrån denna tillverkas polyesterfiber som är det i särklass mest använda materialet inom textiltillverkning. Att plastfragment från textilier skadar havsmiljön är en ny upptäckt och ämnet behöver undersökas i fler dimensioner än vad forskningen hittills gjort. Projektet syftar därför till att klargöra vilka egenskaper som påverkar mängden emission av polyesterfiber vid hushållsnära tvättning. Detta uppnås genom experimentella undersökningar av olika materialkombinationer som tvättas under lika omständigheter. Tvättvattnet analyseras och fibrerna räknas för att erhålla en jämförande studie kring polyestermaterials tendens till fällning av fibrer. Tre faktorer stod till grund för framtagning av metod: utveckling och förbättring av nuvarande metod, att efterlikna hushållstvätt samt tillförlitlighet i resultat. Detta har uppnåtts genom att laborationstvättmaskiner använts istället för kommersiella då detta ger ett vetenskapligt mer säkerställt resultat, något som har bejakats i största möjliga mån i varje steg. Alla polyestermaterial är stickade, färgade och mekaniskt bearbetade på Textilhögskolan för att garantera att samtliga material är tillverkade under samma förhållanden. Olika filtreringsmetoder har testats för att fastställa säkerhet i resultatet. Framtagning av material, tvättning, filtrering och analys var de centrala huvudmomenten för det praktiska arbetet. Analysen har gjorts manuellt där varje partikel på filtret har räknats. Resultatet visade att mikrofibergarn generellt fällde mer än filamentgarn. En högre delning vid stickning gav mer emission än en lägre och att material som slitits resulterade i mer shedding. Kombination av dessa tre faktorer; mikrofibergarn, hög delning och material som slitits gav ett resultat markant större mängd fiberemission än de tyger med endast två av dessa faktorer sammansatta. Tygerna som endast innehöll en av dessa faktorer gav betydligt lägre mängd fällning. Fleecematerial stickat i mikrofibergarn visade sig fälla mindre än en slätstickad vara med samma garntyp stickad i högre delning. Metoden som använts vid framtagning av fleecematerial är ifrågasatt, då kvalitén av dessa inte tycktes motsvara en industriellt framtagen fleecevara. Därför ställer man sig kritisk till detta resultat. De tyger som gav störst respektive minst andel emission av fibrer tvättades ytterligare för att studera inverkan av upprepad tvättning. Emissionen ökade med antal tvättar tills den så småningom avtog när fibrer slitits bort. Resultatet visar att man i största möjliga mån inte bör kombinera polyestervaror i trikå med garn 100den/144f, delning 28 som är smärglad. / The marine environment today, has become the end station for plastics, waste from wastewater and general litter. Large quantities of plastic particles of different sizes have been detected in the ocean, with resulting animals ingesting this mistaking it for food. Science shows that a large part of these plastic fragments are of microscopic size, named microplastics, and within this group there are textile fibres that like other plastics are resistant and detrimental to nature. Studies have shown that when washing, the wastewater carries these small textile fibres and allows them to pass trough the purification.   PET is one of the most used plastics and common in polyester fibre manufacture, by far the most used material in textile manufacturing. A new discovery, finds that the plastic fragments damage the marine environment, and the subject needs to be analysed in more detail than research has covered so far. This project aims to clarify which properties affect the amount of polyester fibre emissions when domestic washing. To investigate this, experimental tests were carried out on different material combinations washed under the same circumstances. Water from the wash was analysed and fibres were counted in order to complete a comparative study of polyester materials tend to shed.   Three factors were considered for developing the method: development and improvement of existing method, aiming to resemble household wash and ensure reliability of results, all done by laboration washers instead of using commercial washing machines. Safety of results has been considerably affirmed during every step. Every polyester material was knitted, coloured and mechanically processed by the research group to guarantee that all of the materials was manufactured under same conditions. Different filter methods have been used to determine safety in results. Manufacturing of material, washing, filtering and analysis were the central focus for the practical work. The analysis came from manual count of every fibre particle.   The result showed that microfiber yarn generally shed more than the filament yarn. A higher gauge gave more emission than a lower and that a worn material resulted in more shedding. The combination of these three factors; microfiber yarn, high gauge and a worn material gave markedly higher results than when tested with only two factors. The tests that only contained one of these factors gave significantly lower amount of emission. Fleece knitted in microfiber yarn had a lower level of shedding than a single jersey material in same yarn type with higher gauge. The method used for manufacturing is questioned, because the quality that should correspond an industrial produced fleece was not matched. Therefore, the result is critically inspected. The two combinations from the chosen parameters that gave the most respective and the least amount fibre emission were analysed additionally with more wash to assess their further effect. Here the emission seemed to increase with the amount of wash until it eventually subsided when more or less the fibres had worn away. Based on this result, one can finally say that these three factors should not be combined to manufacture knitted material in polyester.

Plaster i marina miljöer är ett mycket uppmärksammat problem. På senare år har även mikroplaster uppmärksammats som ett stort miljöproblem. Mikroplasterna kan anrikas med diverse föroreningar i vattnet, de misstas även för föda och tar sig in i näringskedjan. Hälsoeffekterna av detta är ännu okända, men allt mer forskning pekar på att det kan ha en negativ inverkan. En stor andel av mikroplasterna i haven kommer från tvätt av syntetkläder. De följer med tvättvattnet ut ur maskinen och då de flesta reningsverk inte effektivt filtrerar bort dessa partiklar så förs de vidare ut i våra vattendrag. Utifrån de studier som gjorts på mikroplastemission vid hushållstvätt är det svårt att göra några jämförelser eftersom det inte finns någon standardiserad metod. Det anses viktigt att ta fram standardiserade testmetoder för att kunna få jämförbara resultat vid utvecklandet av textila material som släpper minimalt med fibrer i tvätt. Tygprover av polyetylentereftalat analyserades med syftet att utvärdera och validera en metod för att mäta fibersläpp i tvätt, framtagen hos Swerea IVF genom forskningsprogrammet Mistra Future Fashion. Metoden bygger på gyrowashtest i kombination med optisk mikroskopi med tillhörande mjukvara som automatiskt kvantifierar antalet partiklar. Enligt den statistiska analysen misslyckades försöket att upprepa metoden utan signifikanta skillnader. Troligtvis berodde detta på skillnader i förutsättningar, som exempelvis att en laserskärare nyttjades i detta projekt. För att underlätta förbehandlingen och öka repeterbarheten togs en fixtur fram för dammsugning. Fixturen gjorde även att spridningen på provresultaten minskade. Dock visade resultaten på interaktion mellan material och dammsugningsmetod vilket gör det opassande att dra entydiga statistiska slutsatser beträffande de enskilda huvudfaktorerna. Fixturen ger inga skillnader i antalet observerade fibersläpp för återvunnen polyester, men i resultatet för ny polyester syns en signifikant skillnad vid användandet av fixturen. På grund av interaktion och avvikelser för fler än en konstruktionsparameter i materialparen så går det inte att dra några signifikanta slutsatser om eventuella skillnader mellan ny och återvunnen polyester. Metoden är inte lämplig för att mäta den reella fiberemissionen vid hushållstvätt och endast funktionell för att kartlägga skillnader då en parameter i taget varieras. Vidare bör man undvika att göra jämförelser mellan försök utförda med olika förutsättningar innan dess inverkan ordentligt fastställts. / Plastics in the marine environment are an issue that has gotten a lot of attention. Lately microplastics have also been observed as an environmental problem. Contaminants in the water can be adsorbed onto the microplastics, they can also be mistaken for food and enter the food web. The health effects of this are still unknown, but research suggests that it can have a negative impact. A large proportion of the microplastics in the oceans are derived from synthetic clothing. They are shed from the garments during laundry and since most wastewater treatment plants do not efficiently filter out these particles, they end up in the ocean. Today there is no standardized method of measuring shedding and therefore difficult to make any comparisons between studies. It is considered important to develop standardized testing methods to obtain comparable results in the development of textile materials that shed less. Fabric samples of polyester were analyzed for the purpose of evaluating and validating a method of measuring shedding in laundry, developed by Swerea IVF through the research program Mistra Future Fashion. The method is based on gyrowash combined with optical microscopy and connected software that quantifies the number of particles. The method could not be reproduced at the University of Borås without significant differences in shedding. This is probably due to differences in conditions, such as the use of a laser cutter in this project. To facilitate pre-treatment and increase the reproducibility, a fixture was developed for vacuuming. The fixture also reduced the statistical dispersion of the test results. However, the results showed an interaction between the material and the method of vacuuming, thus making it inadvisable to draw any conclusions regarding each individual factor. For the recycled polyester there is no difference in shedding with the use of the fixture, but in the case of virgin polyester a significant difference is observed. Due to interaction and deviations of more than one construction parameter in the paired materials, it is not possible to draw any conclusions regarding differences in shedding between virgin and recycled polyester. The method is not suitable for measuring the actual shedding in household laundry and only functions to compare differences when one parameter is varied solely. Furthermore, comparisons between trials carried out under different conditions should be avoided unless their impact has been properly established.

L’objectif de cette étude est de synthétiser de nouveaux polymères aux propriétés spécifiques, en utilisant pour la première fois comme monomère un aldocétène : l’éthylcétène. La synthèse de l’éthylcétène a été entreprise en utilisant deux procédés distincts :d’une part la méthode de McCarney, qui a permis de le préparer dans un solvant par entraînement à la vapeur, et d’autre part le craquage de l’anhydride butyrique à 575°C sous 40mbar.La polymérisation ionique de l’éthylcétène a ensuite été réalisée, dans différentes conditions de solvant, de température et avec plusieurs amorceurs. La polymérisation anionique a abouti uniquement à la formation d’un polyester amorphe, tandis que la polymérisation cationique a conduit exclusivement à un polymère de structure polycétone,d’une grande stéréorégularité avec une cristallinité moyenne de 0,34. Une caractérisation fine de ces polymères a été effectuée par IRTF-ATR, RMN, TGA, DSC, GPC et diffraction desRX. / The aim of this study is to synthesize new polymers with specific properties, using for the first time an aldoketene as monomer, namely ethylketene.The synthesis of ethylketene was carried out by using two distinct processes: on the one hand the method of McCarney, which led to its synthesis in a solvent by co-distillation, and on the other hand the pyrolysis of butyric anhydride at 575°C under 40 mbar.The ionic polymerization of ethylketene was then carried out, using different solvents, temperatures and initiators. The anionic polymerization gave only amorphous polyesters,while the cationic polymerization led exclusively to a polyketonic polymer, highly stereoregular with an average cristallinity of 0.34. A precise characterization of thesepolymers was undertaken by FTIR-ATR, NMR, TGA, DSC, GPC and X-ray diffraction.

Polyurethanes (PU) are widely used synthetic polymers. The growing amount of PU used industrially has resulted in a worldwide increase of plastic wastes. The related environmental pollution as well as the limited availability of the raw materials based on petrochemicals requires novel solutions for their efficient degradation and recycling. The degradation of the polyester PU Impranil DLN by the polyester hydrolases LC cutinase (LCC), TfCut2, Tcur1278 and Tcur0390 was analyzed using a turbidimetric assay. The highest hydrolysis rates were obtained with TfCut2 and Tcur0390. TfCut2 also showed a significantly higher substrate affinity for Impranil DLN than the other three enzymes, indicated by a higher adsorption constant K. Significant weight losses of the solid thermoplastic polyester PU (TPU) Elastollan B85A-10 and C85A-10 were detected as a result of the enzymatic degradation by all four polyester hydrolases. Within a reaction time of 200 h at 70 °C, LCC caused weight losses of up to 4.9% and 4.1% of Elastollan B85A-10 and C85A-10, respectively. Gel permeation chromatography confirmed a preferential degradation of the larger polymer chains. Scanning electron microscopy revealed cracks at the surface of the TPU cubes as a result of enzymatic surface erosion. Analysis by Fourier transform infrared spectroscopy indicated that the observed weight losses were a result of the cleavage of ester bonds of the polyester TPU.

Le contexte environnemental actuel contraint l’industrie automobile à trouver des solutions pour réduire les émissions de CO2 des véhicules. Une des voies développées consiste à alléger les véhicules en substituant les matériaux à densité élevée comme l’acier par des matériaux plus légers comme les composites. Parmi eux, les SMC (Sheet Molding Compound), généralement employés pour des applications semi-structurales, aspirent à des applications structurales, à condition d’améliorer leurs performances mécaniques (notamment en choc et en fatigue). Les SMC sont composés d’une phase polymère organique (réseau polyester ou vinylester associé à un additif anti-retrait), de charges inorganiques et de fibres de renfort. Cette étude s’est concentrée sur le rôle de la matrice (phase organique + charges) sur les propriétés à la rupture de formulations SMC à fibres de verre et fibres de carbone. Trois axes de recherche ont été développés : i) Analyse de l’existant en évaluant le rôle de l’additif anti-retrait et celui des charges sur les propriétés mécaniques de matrices SMC, ii) Renforcement de matrices SMC par l’utilisation de particules core-shell (CSR), iii) Evaluer le rôle de la matrice sur les SMC à partir des précédents résultats. Dans un premier temps, il a été montré que l’ajout d’un additif de type polystyrène, initialement immiscible dans une résine polyester, conduit à une diminution de la résistance au choc. L’impact de l’augmentation du taux d’un additif initialement miscible (polyester saturé ou polyacétate de vinyle) de faible Tg est gouverné par deux effets antagonistes : la présence de plus en plus importante d’une phase souple renforçante et le développement de microvides qui dégradent les propriétés mécaniques. Puis, l’effet des charges inorganiques a été analysé. Il a été montré que l’ajout de CaCO3 conduisait à une amélioration de la résistance à la propagation de fissure. La résistance à l’amorçage de fissure semble être liée au retrait de polymérisation. La diminution des propriétés à la rupture en présence de microsphères de verre a été démontrée. L’utilisation de charges alternatives a également été explorée. Dans un second temps, des matrices vinylester ont été renforcées par des particules core-shell, qui ont démontré leur efficacité en augmentant considérablement la résistance au choc et la ténacité des systèmes. Des analyses microscopiques ont permis d’identifier des mécanismes de renforcement. Enfin, le rôle de la matrice sur les SMC a été évalué. Ainsi, une augmentation du taux d’additif dans les SMC renforce la matrice et modifie probablement la résistance de l’interface fibre-matrice, entraînant une augmentation de la résistance au choc. L’ajout CaCO3 dégrade cette propriété. De plus, celui-ci masque l’effet renforçant des particules core-shell. Enfin, sur composites à fibres de carbone sans CaCO3, l’ajout de particules CSR permet d’augmenter jusqu’à 20% leur résistance au choc et d’améliorer leur tenue en fatigue. / Because of the current environmental context, automotive industry has to find solutions to reduce CO2 emissions of vehicles. In order to address this issue, one of the possible ways concerns the reduction of the overall weight of cars by substituting heavy steel parts by lightweight composite materials. Among composite materials, Sheet Molding Compounds (SMCs) are used in cars (semi-structural parts) thanks to their low cost and low weight. Their use in structural applications is relevant, provided that their mechanical properties are improved (especially in impact and fatigue). These composites are generally constituted of a polymer matrix (unsaturated polyester or vinylester resin blended with an anti-shrinkage additive) reinforced by short fibers and mineral fillers. The aim of this work was to evaluate the role of the matrix on the mechanical properties of carbon fibers (FC-SMC) and glass fibers-based SMC composite (FV-SMC). Three points were developed : i) a study of existing SMC formulations by assessing the influence of low-profile additive and inorganic fillers on the matrices mechanical properties, ii) a study of the toughening of SMC matrices by adding core-shell rubbers particles (CSR), iii), from the previous results, a last part to assess the impact of the matrix on SMC mechanical properties. First, it was shown that adding a polystyrene (PS) low-shrinkage additive, initially immiscible with a polyester resin (before polymerization), leads to a reduction of Charpy impact resistance, because of PS domains which act as defects. When an initially miscible low-Tg additive is used (PVAc or saturated polyester SP), two antagonist effects were found. When the amount of PVAc or SP was increased, a competition between composition (the presence of a soft phase is more important) and morphology (larger microvoids are created, which lead to a drop of fracture toughness) controlled the evolution of mechanical properties. Then, it was shown that CaCO3 improved fracture toughness of materials. Crack initiation resistance seemed to be lied to polymerization shrinkage. Adding glass microspheres led to a drop of mechanical properties. Other types of fillers were also investigated. In a second part, vinylester matrices were blended with CSR particles. An important toughening was obtained in comparison to a standard SMC matrix. Toughening mechanisms like CSR cavitation, plastic deformation of the matrix or crack-bridging were identified with electronic microscopic observations. Finally, the role of the matrix on SMC was studied. Increasing the rate of saturated polyester (low-profile additive) in FC- SMC formulations led to a better Charpy impact resistance, because of the higher matrix toughness and a probable modification of the fiber/matrix adhesion. With CSR particles in FV-SMC, the presence of CaCO3 limited the toughening. On FC-SMC without fillers, CSR particles led to a better Charpy impact resistance and a better fatigue behavior.

Natural fiber-reinforced composites are now finding extensive uses in various fields from household articles to automobiles. These composites can score high compared to common synthetic fiber-based composites, notably glass fiber-reinforced composites, in areas such as occupational safety and health, and impact on environment. The current research work is motivated by the need for exploring jute fibers as replacement for glass fibers for various engineering design applications including more demanding impact protection applications as in automotive body structures. In the current work, detailed mechanical characterization of jute-polyester (JP) composite laminates till failure has been carried out for tensile, compressive and flexural loads by varying volume fraction of jute fibers. The effect of fiber volume fraction on mechanical properties is shown. Because of the potency of closed thin-walled components as structural energy-absorbers, a comprehensive experimental study has been performed, for the first time, comparing the behaviors of various geometric sections of JP and glass-polyester (GP) composite tubes under axial quasi-static and low velocity impact loading. Additionally, for jute-reinforced plastic panels to be feasible solutions for applications such as automotive interior trim panels, laminates made of such materials should have adequate perforation resistance. Thus, a detailed comparative study has been carried out for assessing the performance of JP laminates vis-a-vis GP plates under low velocity impact perforation conditions. As high-end product design is heavily driven by CAE (Computer-Aided Engineering), the current research work has also focused on the challenging task of developing reliable modeling procedures for explicit finite element analysis using LS-DYNA for predicting load-displacement responses and failures of JP composites under quasi-static and impact loading conditions. In order to extend the applications of JP composites to structurally demanding applications, hybrid laminates made of jute-steel composites and jute with nanoclay-reinforced polyester have been investigated and the considerable enhancement of mechanical properties due to hybridization is shown. Furthermore, a comprehensive study has been conducted on the behavior of JP laminates for varying degrees of moisture content until saturation, and the efficacy of hybrid laminates in this context has been shown.

Auf Grundlage der beiden Monomere (2,2-Bis(hydroxymethyl)propansäure (1) und 4,4-Bis(4-hydroxyphenyl)valeriansäure (2)) wurden hochverzweigte Polyester synthetisiert. Durch Verwendung von zwei-, drei-, vier- und sechsfunktionalen Kernmolekülen konnte die strukturelle Vielfalt der hochverzweigten Polyester erhöht werden. Abmischungen auf der Grundlage zweier Polyole (Polyether- bzw. Esterdiol) mit verschiedenen hochverzweigten Polyestern wurden hinsichtlich ihrer Mischbarkeit mittels DSC- und DMA-Messungen sowie rheologisch, mittels temperaturabhängiger IR-Spektroskopie, hinsichtlich ihrer Oberflächenspannung und mittels temperaturabhängiger AFM-Messungen bzw. SAXS-Messungen charakterisiert. DSC und DMA-Messungen des Glasübergangszustandes der Abmischungen gaben Hinweise, dass hochverzweigte Polyester unterschiedlicher Strukturen mit den Polyolen auf molekularer Ebene mischbar sind. Die hochverzweigten Polyester P1 und P1-PEG400 verbesserten die Verarbeitungseigenschaften eines geschlossenzelligen PU-Hartschaumstoffes. Durch die Hochfunktionalität der hochverzweigten Polyester erfolgte das Aushärten des Schaumstoffes schneller, wobei überraschenderweise das "Fließen" des Schaumstoffes gleichzeitig verbessert werden konnte. Durch den Zusatz der genannten hochverzweigten Polyester zu dem Polyetherpolyol konnte die Viskosität gesenkt werden, was die Fließeigenschaften des Schaumstoffes verbessert. Die Schaumstoffe zeigen weiterhin verbesserte mechanische Eigenschaften.